Writing instrument



FIG. 1 is a side view of the writing instrument with the cover on one end;

FIG. 2 is a side view of the writing instrument with the cover on the other end;

FIG. 3 is a side view of the writing instrument without the cover; and,

FIG. 4 is a side view of the cover of the writing instrument.

The parts are shown separately in FIGS. 3 and 4, for ease of illustration.

The material in broken line forms no part of the design. 

The ornamental design for a writing instrument, as shown and described. 